Electrical coil



March 27, 1934. s. wYss ELECTRICAL COIL Filed Feb. 12. 1930 M 6am Patented Mar. 27, 1934 1,953,035 ELECTRICAL con.

George Wyss, Fort Wayne, Ind., assignor to General Cable Corporation, New York, N. Y., a corporation of New Jersey Application February 12, 1930, Serial No. 427,716

1 Claim.

This invention relates to spools for winding coils of wire and to electrical coils. It is an object of this invention to provide an improved spool upon which coils of wire may be wound, and an improved electrical coil. Other objects and afdtvantages of the invention will appear hereina er.

An illustrative embodiment of the invention selected merely for descriptive purposes is shown in the accompanying drawing, in which:

Fig. 1 is a view of a blank for an end flange for the spool;

Fig; 2 is a side view' of a partially assembled spool; and

Fig. 3 is a view of a coil on a winding arbor or mandrel, the body of the coil being shown in cross section so as more clearly to illustrate. the construction of the spool.

In winding certain types of wire coils, and particularly certain types of flne wire electrical coils for use in electrical apparatus, it is customary to wind the wire in a plurality of overlying layers ginla spool or bobbin, usually of insulating mate- In coils of this type the spool serves as a support to preserve the shape of the coil during the coil finishing operations and during shipment and installation, and also to protect the turns of the coil during such operations against physical injury which might affect the electrical characteristics of the coil or injure it beyond repair. It is desirable that the physical dimensions of the spool be as small as is possible consistent with the requirements for support and protection of a the coil in order that the overall dimensions and weight of the coil may be kept down to a minimum.

Heretofore the spools have been made as integral structures, or have been permanently asmisembled and shipped as spools to the point at which the winding operation is to take place.

Obviously, the shipping bulk of the spools is much greater than that which would be required for the component parts of disassembled spools, and

5 iit is impossible for the operator of the winding machine to adjust the spool flanges accurately to the desired length of coil. According to this invention a spool is provided which may be compactly packed in disassembled condition for shipgoment, and which nevertheless is capable of rapid and accurate assembly without special apparatus immediately prior to the coil winding operation.

The spool is cheap and light in weight, and affords a maximum of protection to the coil turns. 65 Referring to the drawing, and particularly to Figs. 2 and 3, the spool comprises a rigid tubular member 11, conveniently of paper or fibre, and two end flanges 12a and 12b, preferably of flexible sheet material such as paper or fibre, slipped loosely on the ends of the tube.

Conveniently the end flanges are alike and are formed from annular disks 12, (Fig. 1) by striking a series of radial slits 13 along the inner marginal portion of a disk to form inwardly projecting tongues 14, and by bending all of the tongues 14 in one direction at substantially right angles to the disk to form a circumferentially discontinuous sleeve-like extension from the new inner edge of the disk. The radial depth oi the slits 13 is chosen so that the inside diameter of the sleeve-like extension in the plane of the disk is substantially equal to the outside diameter of the tube 11. An end flange with the tongues bent to form the sleeve-like extension and ready for assembly on a tube 11 is shown in the lefthand portion of Fig. 2.

The spool may be easily and quickly assembled immediately prior to the wire winding operation by pressing the tongues 14 of the end flanges outwardly, and by inserting the ends of the tube 11-in the sleeve-like extensions of the disks so that when the tongues 14 are released they lie inwardly along and lightly grip the outer surface of the tube 11. It will be seen that this gripping action of the tongues Men the tube 11 will serve temporarily to position the end flanges on the tube, while at the same time permitting sliding movement of the flanges longitudinally-along the tube to adjust accurately for the desired coil length.

The spool may be partially or completely assembled directly on a suitable winding arbor, or the spool may be assembled and then positioned on the winding arbor.

Fig. 3 shows an electrical coil wound on an assembled spool, the spool being supported on one suitable form of winding arbor which is shown merely by way of example. The arbor which is shown comprises a shaft 15 having at its left and righthand ends respectively the male and female centers?! and 18, and also having at its left end a collar 16 provided with a driving dogpin 19. Carried on the left end of the shalt 15 adjacent the collar 16 is a hub 20 having at its outer end adjacent the collar 16 a flange 21. The hub 20 is fixed rigidly on the shaft 15, as by means of a pin 22, and at its inner end conveniently has a key 23 engaging a complementary key slot on the inner end of a hub 24- which is slidably mounted on the shaft. The outer end of the hub on the other spool flange and the tube 11.

24 has a flange 25 similar to the flange 21, and may be rigidly secured on the shaft during the winding operation, as by means of a nut 26. The nut 26 may be provided with suitable means for tightening and loosening, for example a dogpin 27.

Preferably the hubs and 24 are tapered slightly inwardly so that when the arbor is assembled the hubs frictionally engage the inner wall ofthe tube 11 of the spool to prevent the spool turning on the arbor. Conveniently the inner faces of the flanges 21 and may .be recessed slightly to receive the end flanges of the spool.

In winding a coil the operator places the two end flanges 12 on a tube 11 as hereinbefore described, conveniently sliding the flanges slightly inwardly from the ends of the tube. The spool is then placed on the arbor, and the arbor is assembled and placed in the winding machine. The operator then slides one of the spool flanges outwardly against its arbor flange, and threads the wire from which the coil is to be wound outwardly through between two of the tongues 14 The wire end is drawn through between the spool flange and tube a distance suflicient to provide a lead for a terminal connection, and the wire end conveniently is wrapped loosely two or three turns about the tube 11 between the spool flange the. flanges 12, the length of the coil being accurately fixed by the arbor flanges 21 and 25. The end turns of the first coil layer overlie the tongues r 14 in the angle between the tongues and the disk 12 and bind the tongues down on the tube 11 to hold the spool flanges firmly against further sliding movement along the tube. It will be apparent that the inner end turns of the coil are completely protected, and cannot slide throughbetween the flanges 12 and the tube 11 after the coil is removed from the arbor.

When the desired number of turns have been wound on the coil the machine is stopped, the wire is severed and the coil lead secured, and the mandrel is removed from the machine and disassembled. The coil may then be tied and finished in any suitable manner.

It will be apparent that a spool is provided which is cheap and light in weight, and which may be readily shippedin disassembled condition. The spool flanges are movable along the spool tube, so that they may be accurately adjusted on the winding machine to the desired length, and are firmly and immovably secured on the tube during the winding operation solely by the binding effect of the coil turns. The end turns of the inner coil layers are completely protected, and cannot slide through between the inner edges of the end flanges and the tube with consequent danger of damage to the wire insulation. I

It will be understood that the invention may be variously modified and embodied within the scope of the claim.

I claim:

An article of manufacture comprising a rigid cylindrical tube, a pair oi. relatively flexible end flanges positioned one on each end of the rigid tube, each end flange comprising an annular disc 5 whose inner marginal portion has a series or radial slits, the tongues defined by said slits severally being bent substantially at right angles to the disk and lying inwardly along and in contact with the outer surface or the tube, an electrical 110 coil winding comprising a plurality of overlying layers of insulated flne wire on said tube extending between the end flanges and overlying the tongues, and a terminal lead from the inner end of the coil winding extending outwardly between 115 the tube and the end flange through one of the slits.

GEORGE WYSS. 

